California Adopts First Rules Limiting Greenhouse Gas Emissions from Cars and Trucks

Date: 27 Sep 2004 | posted in: Energy, Energy Self Reliant States | 0 Facebooktwitterredditmail

On September 24, 2004 the California Air Resources Board announced that they had approved a landmark regulation that requires automakers to begin selling vehicles with reduced greenhouse gas emissions by model year 2009.

ARB Chairman Dr. Alan Lloyd said, "This landmark decision sets a course for California that is likely to be copied throughout the US and other countries. Because of its forward-thinking approach, the ARB has established itself as the world leader in setting motor vehicle pollution control standards. Those standards have led to automotive technologies that dominate the way cars are built today and have significantly cut air pollution’s public health risk. This regulation will have the same impact."

The historic regulation sets limits on the amount of greenhouse gas emissions that can be released from new passenger cars, SUVs and pickup trucks sold in California starting in model year 2009. The new regulation is based on a state of the art assessment of the various technologies and fuels that can reduce motor vehicle global warming pollutants.

According to ARB staff, the average reduction of greenhouse gases from new California cars and light trucks will be about 22 percent in 2012 and about 30 percent in 2016, compared to today’s vehicles. Costs for the added technology needed to meet the rule are expected to average about $325 per vehicle in 2012 and about $1050 per vehicle to comply in 2016. The ARB staff analysis concludes that the new rule will result in savings for vehicle buyers by lowering operating expenses that will more than offset the added costs of the new vehicles and provide an overall cost savings to consumers.

The adoption of this rule makes California the nation’s only state that has regulated motor vehicles for their contributions to global climate change. At least seven other states including New York, Massachusetts, New Jersey, Vermont, Connecticut, Rhode Island and Maine, as well as the nation of Canada, are expected to consider adopting the regulation for their use. If all of those states and Canada adopt the rule, the number of cars required to meet the rule will triple.


  • For more detail on the legislation and rules see New Rules Project section on Automobile Greenhouse Gas Emissions – California
  • Background Documents from ARB – September 2004
  • Staff Report: Initial Statement of Reasons (ISOR)
  • Appendix 1– Proposed Regulation Order
  • Appendix 2 – California and Exhaust Emission Standards and Test Procedures for 2001 and Subsequent Model Passenger Cars, Light-Duty Trucks, and MediumDuty-Vehicles
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John Farrell

John Farrell directs the Energy Democracy initiative at the Institute for Local Self-Reliance and he develops tools that allow communities to take charge of their energy future, and pursue the maximum economic benefits of the transition to 100% renewable power.